rodo 666 mod need help

[8bitforlife]

Has anyone preformed the mod to a rodo or weiya chassis to have a switch for 15hz and 31hz to fix the compression on the side. @XianXi and I have been trying to figure it out but the wiki is garbage on instructions. If anyone has preformed this mod we could use some pictures or info to clarify.

https://wiki.arcadeotaku.com/w/Rodotron_666

 

[nem]

What do you mean garbage instructions? It's two polyester caps and a switch? I've never done the mod and looks as clear as day to me.

Originally there's only the one poly cap. You take that one out. You're left with two holes. You put a wire in the hole next to the transistor on the left. That goes to the center leg of the switch. Then you have two wires going from the outer legs of the switch to the new poly caps. You put the poly caps vertically on the PCB. One cap populates the other hole that was there to begin with, the other goes in a different, originally unpopulated, hole (both holes share the same trace). You throw the switch everytime you change resolution.

 

[8bitforlife]

well @XianXi knows what hes doing but we are having trouble because the pictures arent clear

 

[XianXi]

What do you mean garbage instructions? It's two polyester caps and a switch? I've never done the mod and looks as clear as day to me.

Originally there's only the one poly cap. You take that one out. You're left with two holes. You put a wire in the hole next to the transistor on the left. That goes to the center leg of the switch. Then you have two wires going from the outer legs of the switch to the new poly caps. You put the poly caps vertically on the PCB. One cap populates the other hole that was there to begin with, the other goes in a different, originally unpopulated, hole (both holes share the same trace). You throw the switch everytime you change resolution.

Not all 666/666A pcbs are silkscreened underneath. This is why it isn’t clear. It’s a little harder to index since it doesn’t say left leg of C86 etc.

Your instructions are a little easier to understand than in the link.

 

[XianXi]

Just to be clear, which cap am I removing? C88, C86, C85 or C87?

You say the one next to the transistor which is C88 but the transistor isn’t pictured in the instructions unless you are referring to the diode next to C85.

 

[8bitforlife]

Different layout than the mod says

 

[nem]

There are a ton of variations of this chassis. I would first confirm that this one has side compression at 15khz and then swap the poly cap for the recommended one (1uF) and check that it fixes it.

Anyway, the cap is C86, it should be a 0.43uF cap. Both details are mentioned in the wiki.

As for my reference to the transistor, I was talking about the solder hole that's nearest to the transistors on the side of the chassis. That's the one you want to go to the center leg of the switch.

 

[XianXi]

There are a ton of variations of this chassis. I would first confirm that this one has side compression at 15khz and then swap the poly cap for the recommended one (1uF) and check that it fixes it.

Anyway, the cap is C86, it should be a 0.43uF cap. Both details are mentioned in the wiki.

As for my reference to the transistor, I was talking about the solder hole that's nearest to the transistors on the side of the chassis. That's the one you want to go to the center leg of the switch.

Thanks dude. Ya the black things mounted to the heatsink in a TO-220 looking packages are actually diodes, that’s why I was confused.

Thanks for the help dude, it’s very much appreciated.